Do not assign positions to parser-generated desugarings.

test/mjsunit/mjsunit.status

 # Copyright 2012 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
 #       disclaimer in the documentation and/or other materials provided
@@ skipping 95 matching lines @@
   'debug-stepin-property-function-call': [PASS, NO_VARIANTS],
   'debug-stepnext-do-while': [PASS, NO_VARIANTS],
   'debug-stepout-scope-part1': [PASS, NO_VARIANTS],
   'debug-stepout-scope-part2': [PASS, NO_VARIANTS],
   'debug-stepout-scope-part3': [PASS, NO_VARIANTS],
   'debug-scripts-request': [PASS, NO_VARIANTS],
   'es6/debug-stepin-microtasks': [PASS, NO_VARIANTS],
   'es6/debug-stepnext-for': [PASS, NO_VARIANTS],
   'es6/debug-evaluate-blockscopes': [PASS, NO_VARIANTS],
   'regress/regress-crbug-259300': [PASS, NO_VARIANTS],
+  'es6/regress/regress-468661': [PASS, NO_VARIANTS],
 
   ##############################################################################
   # Too slow in debug mode with --stress-opt mode.
   'compiler/regress-stacktrace-methods': [PASS, ['mode == debug', SKIP]],
   'compiler/regress-funcaller': [PASS, ['mode == debug', SKIP]],
   'regress/regress-2318': [PASS, ['mode == debug', SKIP]],
   'regress/regress-create-exception': [PASS, ['mode == debug', SKIP]],
 
   ##############################################################################
   # Too slow in debug mode for GC stress mode.
@@ skipping 473 matching lines @@
 ['arch == ppc and simulator_run == True or arch == ppc64 and simulator_run == True', {
 
   # take too long with the simulator.
   'regress/regress-1132': [SKIP],
 
   # these two issues started after uplevel, believe they share common cause
   'debug-references': [SKIP],
   'mirror-object': [SKIP],
 }],  # 'arch == ppc and simulator_run == True'
 ]